Question

Two thin lenses have a combined power of +9 D. When they are separated by a distance of 20 cm. their equivalent power becomes $+\frac{27}{5}D$. Their individual powers (in dioptre) are

• A. $1.8$
• B. $2.7$
• C. $3.6$
• D. $4.5$

Answer 1

The correct option is C $3.6$

option C is correct